Newsbrief: Sony announced today that, as of January 15, more than two million copies of Guerrilla Games' sci-fi shooter Killzone: Shadow Fall have been sold worldwide across both digital and retail channels.

That's an average of more than a million sales per month for the PlayStation 4 game, which was released on November 15 in North America.

That's good news for Guerrilla Games -- studio co-founder Herman Hulst told us the studio spent roughly as much or more developing Shadow Fall as it had on any previous console Killzone game when we spoke to him early last year about the costs of next-gen development.